Machine tool



Nov. 17, 1942. B. P. GRAVES rs1-rm.

MACHINE TOOL original Filed oct. 7, 1939 5 Sheets-Sheet 1 NNN , www

Inventors Witness M 7.

NOV- 17, 1942- B. P. GRAVES E-rm.

MACHINE TOOL Original Filed Oo'b. '7, 1959 .5 Sheets-Sheet 2 Wzltn ess NOV. 17, 1942. B. GRAVES ETAL 2,302,026

MACHINE Tool.

Original Filed 001'.. 7, 1939 Sheets-Sheet 3 Fig. ,4

l Inventors uy-MQ.. )2' am).

Nov. 17, 1942. B, P, GRAVES ET AL 2,302,026

MACHINE TOOL Original Filed Oct. 7, 1939 5 Sheets-Sheet 4 Fly. 7 h 24o 3i F 6 Z36/- Fig. 9

Nov. 17, 1942. B. P. GRAVES ET Al.

MACHINEv TOOL original Filed oct. 7, 1959 5 Sheets-sheet 5 t 318 Inventors l al 4W L'Mr Witne 62m@ j Mw@ atented Nov. 17, 1942 MACHINE TOOL Benjamin P. Graves, Barrington, and Hans Carl Weimar, Providence, R. I., assignors to Brown and Sharpe Manufacturing Company, a corporation of Rhode Island Original application October 7, 19-39, Serial No.

298,460. Divided and this 1941, Serial No. 401,190

9 Claims.

The present invention relates to a honing attachment adapted for use in a machine tool of the general type having relatively movable tool and work supports.

Applicants honing attachment forming the subject-matter of the present invention is herein disclosed in a preferred form as applied to a cylindrical grinding machine comprising a work support having a rotary work holder mounted thereon, a grinding wheel spindle, and a carriage support for the spindle, together with operating means for imparting relative translatory and cross feeding or positioning movements to said supports.

It is the object of the present invention to provide a novel and improved honing attachment which is rugged and simple in construction, and is well adapted for the eflicient performance of a secondary honing or finishing operation upon a work piece.

With these and other objects in View as may hereinafter appear, the several features of the invention consist in the devices, combinations and arrangement of parts hereinafter described and claimed, which together with the advantages to be obtained thereby will be readily understood by one skilled in the art from the following description taken in connection with the accompanying drawings, in which Fig. l is a View in right side elevation of a cylindrical grinding machine having mounted thereon applicants improved honing attachment; Fig. 2 is an enlarged detail view in front elevation of the honing attachment; Fig. 3 is a detail sectional plan View taken on the line 3 3 of Fig, 2; Fig. d is a detail View looking from the left showing substantially the parts of the honing attachment illustrated in Fig. 2; Fig. 5 is a detail sectional plan View taken on the line 5 5 of Fig. e; Fig. 6 is a seotional plan view taken on the line 6 9 of 7; Fig. 7 is a detail sectional View in front elevation taken through the honing attachment, and illustrating particularly the mechanism for raising and for lowering the honing attachment into operating position, the mechanism for adjusting the limits of vertical movement of the honing attachment, and the operating switch connection for starting and stopping the honing motor; Fig, 8 is a detail view partly in section of the operating switch shown in Fig. 7; Fig. 9 is a detail sectional plan view taken on the line 9 9 of Fig. 2, illustrating a portion of the driving mechanism for reciprocating the honing device; l0 is an enlarged plan View of the honing attachment, with portions of the same broken away, and illustrating particularly the means for supporting the attachment on the grinding wheel guard plate; Fig. 1l is a detail sectional View in front elevation taken on the line Il ll of Fig. 10; and Fig. 12 is a sectional plan view taken on the line |2 |\2 of Fig. l1.

application July 5,

The invention is herein disclosed as embodied in a cylindrical grinding machine having a base 13, a recip-rocable work table 80, a rotary work holder comp-rising a headstock generally indicated at 82, a tailstock 84, a cross feed slide or carriage 88, a grinding wheel 90, a wheel yspindle Q2, and a spindle driving motor 94 supported on the cross feed slide 88. The machine is provided with means for effecting cross feeding movements of the wheel spindle carriage, these parts including the nut 203 and cross feed screw 262 being shown in Fig. l, and is additionally provided with cross feed rapid movement mechanism for moving the grinding wheel carriage and grinding wheel rapidly through a predetermined distance toward and away from the work. rhis mechaanism, as generally indicated in Fig. 1, includes a cross feed motor 2|4, a worm 216, a worm gear 2|8, a crank 220 driven thereby, a link 222, and an actuating lever 224 having a sleeve connection 226 with the cross feed screw 292 for effecting axial movement thereof bodily between forward and-back limiting positions.

Inasmuch as the invention which forms the subject-matter of the present application is concerned particularly with the construction and arrangement of the honing attachment per se, further illustration and description of the cylindrical grinding machine to which it has been applied is herein omitted. Features of applicants invention concerned with an improved control system for a machine of this general type which will adapt the machine for automatic operation in accordance with an added honing cycle of operation forrn the subject-matter of applicants application for U. S. Letters Patent Serial No. 238,460, led October 7, 1939, of which the present appplication is a division.

In carrying out the present invention, applicants have provided a honing attachment which is conveniently secured to the grinding Wheel guard on the wheel spindle carriage, and comprises essentially a honing element having honing stones mounted therein arranged for engagement with one side of the work, and for rapid vibratory or reciprocatory movement axially of the work. In the illustrated form of the invention, the honing element and supporting and actuating mechanism therefor are mounted in a housing which is vertically movable between alternative lowered work engaging and raised inoperative positions. The holder is carried upon the lower end of a spring-seated spindle which is in turn supported upon a pair of parallel levers carried by the housing. The levers are connected through linkage connections to a motor driven crank which serves to impart a rapid vibratory movement to the parallel levers, the spindle supported thereby, and the honing element axially of the work.

Further in vaccordance with the invention, ap-

piicants honing attachment is mounted on the cross feed slide and in such relation to the several operating parts of the machine as to provide an organization of the machine of maximum efiectiveness for the periormance of a honing operation, and which will not have the eiect4 ofl obstructing or interfering with the usual operating functions of the machine. housing is supported for vertical movement on a horizontal slide member which is adjustably secured to guideways in a bracket on the wheel spindle guard. These parts are constructed and arranged so that the rapid movement of the wheel spindle carriage to its fully retracted position will cause the honing attachment including the holder to be located directly above the work in position to be lowered into work engaging contact. When the grinding wheel carriage is in its relatively advanced grinding position, the honing attachment will be located in a relatively advanced inoperative position in front of, and above the work on the machine.

In the illustrated construction, the mechanism for raising and lowering the housing and the vibratory honing device mounted thereon, comprises a hand lever movable between alternative iixed limitinfT positions, and having a rack and pinionoperating connection with the housing. 1n, order to provide for adjustment particularly of the low or work engaging position to which the honing device is moved by the movement of the hand leverV as may be required by diierent diameters of work being operated upon, the rack is movabiy secured to the housing for vertical adjustment with relation thereto.

In accordance with the present invention, operating connections are provided which are rendered operative by the movement of the honing device to its work engaging position to start the honing device in active operation. In the illustrated construction, a switch is provided which is arranged to be closed by movement of the housing and the honing device supported thereon to the low work engaging position, and serves to start the vibratory movement or" the honing attachment.

The honing attachment provided in accordance with the present invention, as generally shown in Figs. l and 2i of the drawings, comprises a vibratory honing element 23d including honing u stones 232, a housing 23a on which the honing element and its supporting and actuating mechanism is carried, a support 23d including guideways 238 on which the housing is vertically movable, and a bracket 25m secured to the usual grinding wheel guard 2li?! of the machine having horizontal guideways 2da (see Fig. l1) in which the support 235 is adjustably secured.

Supporting and actuating connections for the honing element 239, as best shown in Figs. 2, 4 and 5, comprise a vertical spindle 226 having at its lower end a tapered pin and socket connection with the honing element 23@ providing a tiltable connection therewith. The spindle 24S is slidably mounted in a spindle support 24S, and is pressed yieidingly downwardly by means of a compression spring 25d coiled about a reduced shank portion of the spindle between a shoulder 252 on the spindle and a shoulder 25d in the spindle support 223. Downward movement of the spindle in its support is limited by adjustable check nuts 25S screw-threaded to the upper end thereof, and arranged to bear against the abutting upper end of the spindle support 248. As hereinafter more fully set forth, the housing 234 To this end the and connected thereto by a pivot pin 218.

and the honing device supported therein including the spindle support 228 are moved downwardly to an adjustableV work engaging position in which the honing element 232 will be engaged against the work, and in which the spindle 246 will be forced upwardly to some extent against the pressure of the spring 25d to provide a springpressed contact between the honing element and work. The spindle 245 is keyed against rotational movements in its support by means of a pin 258 on the spindle which engages within a slotted portion 25d of the spindle support 2:38. The parts above described including the honing element 235i, spindle 22d, and spindle support 248 are supported for vibratory movements bodily ubstantially in the line of the axis of rotation of the work holder and work by means of two bell-crank levers 252 25d having pivotal supports 26E and 258 respectively in the housing 234. fis seen, for example, in Fig. 2, the levers 262, 254 are located directly above one another in parallel position, having the downwardly extending arms thereof pivotally connected to lugs 219 and 212 formed on the spindle support 223. T dnks 214 connecting the laterally extending arms of the bell-cranks, cause these levers to move as a single unit.

A rapid oscillatory movement is imparted to the honing element 23) by means of a motor driven crank and link connection with the bellcrank levers 262, 26d. Referring speciiically to Figs. 2, 4 9, these connections comprise a link 226 biiurcated at its lower end to straddle the horizontal arm of the bell-crank and links 214, At its upper end the link 212 is pivoted on an eccentric pin or crank 28d formed in a rotatably adjustable circular disk 2ii2 which is in turn eccentrically supported on the face of a driving gear 284 carried on a rotatable shaft 285. As best shown in Fig. 9, the eccentric disk 232 has a tapered peripheral edge which engages with a correspondingly tapered aperture in a clamping plate 286 which is carried on one face of the driving gear 22d, and is rigidly clamped thereto by machine screws 238. With this construction it will be seen that the length of the crank arm provided by the eccentricity of the pin 28d with relation to the driving gear 284 may be readily adjusted to vary the amplification of the vibratory movements imparted to the honing element 230 by adjusting the angular position of the eccentric disk 222 with relation to the driving gear 284.

The driving gear E and crank pin 28%) supported thereon are driven from an electric motor 22] supported on a bed plate 292 hinged at 224 to the upper face of the housing 235. An adjusting screw 2% formed on the outer edge of the bed plate 232 for engagement with the housing 236i provides convenient means for adjusting the tension on a driving belt 293 passing over a stepped pulley 3%@ on the armature shait 32 of the motor, and over a stepped pulley 324 carried on a driven shaft 3G@ in the housing 23d. A pinion 328 formed on the shaft 30d meshes with and serves to drive the gear 255i and crank pin 225.

The housing 234 and the honing device supported thereon are arranged to be moved through a predetermined distance between low work engaging and high inoperative positions through the operation of a manually operable control lever iiii and a pinion SI2 carried on the support 22E for engagement with a rack @i4 adjustably supported in a T-shaped slot 3i6 formed in the housing 234. The lever tid, as best shown in ,stop suriace334.

thereto.

Figs. 2, 6 and 7, is pivotally supported for forward `and Vback movements on a pivot pin 318 Within `a bfurcated bracket 320 formed on one end of .a rock shaft 322 to which is also secured the Apinion 3I2. A spring-pressed plunger 324 mounted in an axial recess in the shaft 322 abuts against a downwardly extending tail 32S of the lever 310 acting to maintain the lever 3|!) in an upright position in which a rearwardly extendingabutment 328 thereof will engage against the ,peripheral edge of a latch plate 330. The control lever `3IU is arranged to be moved through 120 between work engaging and inoperative positions.

In the position shown, for example, in Figs. 2

and "7, with `the lever in its raised or vertical position, the housing 234 and honing device supported thereon, will have been lowered to its low `work engaging position, the extent of this downgagement of the abutment 328 on the lever with one side `of a recess 333 in the latch plate 339. ,The lever is now permitted to rock rearwardly .aboutits pivot SiS, causing the abutment 328 to move into latching position in the recess 333, thus locking the honing device in its raised inoper- .ative position.

In accordance with one feature of the invention, an adjustment is provided for adjusting the downward limit of movement of the honing device to its work engaging position as determined by the throw of the control lever 3H) and the seating of `the rack 3|4 and block 332 against the This adjustment is provided by means of an adjusting screw 34d screw-threaded into the upper end of the rack 3M, and having a bearing ..342 ina supporting plate 34d which is securedto the housing 234 and overlies the upper end of the T-shaped slot Slt for the rack. A knurled head 343 secured to the upper end of the adjusting screw 34) provides a convenient means for effecting this adjustment in the position of the rack 3l4 relative to the housing 34.

As best shown in Figs. 10 to 12 inclusive, the

support 23e for the housing 234 is slidably sup- L ported on the bracket 240 on the wheel guard to permit adjustment of the honing attachment forwardly or rearwardly on the wheel spindle carriage V88, so that the honing device will be accurately placed above the axis of rotation of the work holder and work when the wheel slide rapid vmovement is rendered operative to retract the grinding wheel carriage from grinding posi- .tion to its fully retracted position away from the work. The mechanism for eiecting this adjust- .ment comprises a rearwardly extending rod 34B .-244. VTherod 343 is supported against axial movement with relation to the support 235 by vmeans of a collar 358 which engages with the reduced forward end portion 35S of the rod 343 Vbetween the shouldered end of the reduced por- .tion and a knurled operating knob 35E! secured The support 235 is rigidly clamped in adjusted `position by means of two clamping screwsl362 rotatably mounted in the support 23d, andhaving screw-'threaded engagement with a clamping shim 364 contacting with the guideway 244.

In accordance with the present invention, an operating switch is provided which is arranged to be closed by movement of the housing and honing device supported thereon to the low work engaging position to start the `honing motor 290 in active operation. As best shown in Figs. 7 and 8 of the drawings, the honing switch generally designated at LSI comprises an axially movable plunger 4t2 having mounted on the reduced portion thereof a switch contact cross arm [52d arranged to Contact with connections 5-32. A compression spring 4&5 tends normally to maintain the plunger and switch arm in a low open position. The actuating connections for the switch comprise a switch lever 4% pivoted at 4H) on the support 235 for the housing 234. One end of the switch lever 408 is arranged to engage beneath the switch plunger 4t2, and the other end enters a slotted portion of the abutment 334 for limiting the downward movement of the rack 3M and housing 234. Downward movement of the rack to its limiting position against the abutment 334 acts to rock the switch lever M8 in a counter-cloclnvise direction as illustrated in Figs.

`7 and 3, to close the switch and thereby to start the honing motor 2%.

The several features of applicants honing attachment have been described, and the advantages thereof pointed out by way of illustration in connection with the use of the attachment in a cylindrical grinding machine. The several novel features of construction and operation of the attachment are believed however to be of broad scope, and to render the attachment readily applicable to other types of machine tools having relatively movable tool and vt ork supports.

it will be understood that the invention is not i limited to the specic embodiment shown, and

that various deviations may be made therefrom .without departing from the spirit and scope 0f the appended claims.

What is claimed is:

l. For use in a machine tool having a work support, and a tool support arranged for relative movement, a honing device which comprises a honing element, a spindle having a tiltable connection therewith, a spindle support, means for yieldably supporting the spindle in an extended position in its support, a pair of supporting levers on which said spindle support is mounted for movement substantially in the line of honing contact with the work, means for imparting a vibratory movement to said spindle and its support and honing element supported thereby comprising a prime mover, an eccentric driven thereby and connections from the eccentric for imparting parallel oscillatory movements to said levers, and a housing for said honing device mounted on the tool support movable between work engaging and withdrawn inoperative positions.

.2. For use in a machine tool having a work support, a tool support, and means for effecting relative movement of said supports, a honing attachment arranged to be supported on the tool support comprising a honing element; a spindle to which the honing element is attached arranged substantially perpendicular to the work at the point of honing contact, a pair of bell-crank levers on which the spindle is carried having the Vpivotal axes and spindle supporting arms thereof arranged substantially in one lineperpendicular 'to'the work at the point of 'honing cranks contact, and actuating means including a link connection between the free arms of said bellior imparting simultaneous identical' vibratory movements thereto.

3. -For use in a machine tool having a work support, a tool support, and means for effecting relative movement of said supports in at least one plane, a honing attachment arranged. to be supported on the tool support comprising a honing element, a honing element support ncluding a spindle on which the honing element is carried arranged substantially perpendicular to the surface of the work at the point of honing contact and a yieldable connection engaging the honing element yieldably against the work, a pair of levers on which the honing element support is carried having their pivotal aXes disposed with relation to one another in a line substantially perpendicular to the plane of relative movement of the tool support and work support and having the supporting arms thereof extending substantially perpendicular to said plane of relative movement of the tool support and work support, and means lor imparting simultaneous identical vibratory movements to said levers.

For use in a machine tool having a work support, a tool support arranged for relative movement, a honing attachment arranged to be supported on the tool support comprising a vibratory honing 1'evice including a honing element, a spindle on which the honing elementis carried'arranged substantially perpendicular to the surface oi the work at the point of honing contact, a spindle support, spring means for yieldably supporting the spindle in an extended position in its suppor stop means adjustable to vary the extending movement of the spindle in its support thereby the pressure exerted by 1ing means, supporting and actuating means i'or imparting vibratory movements to said spindle support bodily in the line of honing Contact with the work, and a housing for said honing device movable on the tool support between work engaging and inoperative positions.

5. F or use in a machine tool having a work support, a tool support, and means for effecting relative movement ci said supports, a honing attachment arranged to be supported on the tool support comprising a vibratory honing device including a honing element, a spindle on which the honing element is carried arranged substantially perpendicular to the work surface at the point oi honing contact, a spindle support, spring means yieldably supporting the spindle in an extended position in its support, stop means adjustable to vary the extending movement of the spindle and thereby the pressure exerted by the spring means, supporting and actuating means for imparting vibratory movements to the spindie support bodily substantially in the line of honing contact with the work, a housing for said honing devi e movable with relation to the tool support, shifting means for moving the housing and honing device between predetermined work engaging and inoperative positions, and adjusting means for determining the extent of movement of the housing to work engaging position.

6. For use in a machine tool having a work support and a tool support, and means for eiecting relative movement of said supports, a honing attachment comprising a housing, a vibratory honing element, and actuating means therefor carried by the housing, shifting means for moving the housing between Work engaging and inoperative positions on the tool support comprising a rack on one of said housing and"tool support, and a cooperating pinion and actuating lever therefor carried by the other of said housand tool support, means for limiting the movement oi the lever and racl; actuated thereby between two alternative wort: engaging and inoperative positions, and means for adjusting the posi"on of one oi said rack and pinion with relation to its support whereby to effect an adjustment oi' the work engaging position to which the housing and honing element are moved by said lever.

'7. For use in a machine tool having a work a tool support, and means for effecting relative movement of said supports, a honing attachment on the tool support comprising a housing, a vibratory honing element, and actuating mcans therefor carried by the housing, and shifting means ier moving the housing and vibratory honing element between work engaging and raised inoperative positions on the tool support comprising a rack on the housing, a pinion carr'ed by the tool support, a manually operable lever connected with the pinion movable between limiting work engaging and inoperative positions, and adjusting means for moving the rack with relation to the housing to adjustably determine the limiting positions to which the housing and honing element are moved by the lever.

8. For use in a machine tool having a work support, a tool support, and means for effecting relative movement oi said supports, a honing attachment comprising a housing, a vibratory honing element, and actuating means therefor carried by the housing, and shifting means for moving the housing and vibratory honing ele- :ient between work engaging and inoperative positions on the tool support comprising a rack slidably supported on the housing, an adjusting screw for determining the position of the rack with relation to the housing, a cooperating pinion carried by the tool support, a manually operable lever connected to rotate the pinion movable between tvvo limiting positions, a stop carried by the tool support for engagement with the rack to limit movement oi the rack and lever in work engaging position, and a latching device associated with the lever for locking the lever and rack in inoperative position.

9. For use in a machine tool having a work support, a tool support, and means for effecting relative movement of said supports, a honing attachment comprising a housing, a vibratory honing element and actuating means therefor including an electric motor carried by the housshifting means for moving the housing between worl: engaging and inoperative positions on the tool support comprising a rack on the housing, a pinion carried by the tool support, a manually operable lever connected with the pinion movable between limiting work engaging and inoperative positions, adjusting means for moving the rack with relation to the housing to adjustably determine the limiting positions to which the housing and honing element are moved by the lever, a startand stop switch connection for the motor, and an actuating element for said switch arranged to be actuated by the rack upon movement to work engaging position to start the motor, and by movement of the rack away from said work engaging position to stop the motor.

BENJAMIN P. GRAVES. HANS CARL WEIMAR. 

